Arrangement in a device for threading a web of material by means of a socalled pilot



A. BRAUER ETAL 3,199,219

Aug. 10, 1965 ARRANGEMENT IN A DEVIUE FOR THREADING A WEB OF MATERIAL BY MEANS OF A SO-CALLED PILOT Filed March 19, 1962 FIGS.

INVENTORSJ BRAUER ANDERS ROLF PEHRSON United States Patent Office 3,l39,2l Fatented Aug. 10, 1065 3,199,219 ARRANGEMENT EN A DEVICE FUR THREADENG A WEB 0F MATEREAL BY MEANS OF A S0- CALLED PILGT Anders Eraucr, Stockholm, and Rolf Pehrson, Mullsiii,

Sweden, assignors to Ahtieholaget Svenska Flalrtfabriiren, Stockholm, Sweden Filed Mar. 19, 1962, Ser. No. 181,230 2 Claims. (Cl. 34-120) The present invention relates to an improved arrangement in a device for threading a web of material by means of a so-called pilot according to US. Patent No. 3,085,- 346, April 16, 1963, intended for a drier or other treatment plant, where the web is carried forward airborne in a number of passages between turning rolls arranged at the ends of each passage.

In practice when using such a pilot for threading it h-as proved that the pilot, which must be made relatively rigid in order to be driven forward in the straight passages in the manner intended with the aid of the treatment me dium supplied, is not always automatic-ally transferred from one passage to another, but sometimes continues straight forward on to the end Wall of the plant Where it is pressed against the Wall and thereby is stuck. As an unfortunate incident of this kind, unless it is immediately discovered and corrected, can jeopardize the entire threading operation with subsequent stoppage and ditticulties, it has been a pressing problem to eliminate the said hazard in some way and to ensure fully automatic and reliable threading.

The invention, which has solved the said problem by simple means, is characterized in that generally semicircular return or direction-reversing baffles or enclosures are provided outside the turning rolls in order to form a closed return duct for the pilot, and that a number of blast nozzles for the purpose of producing a forwarddriving current of air are applied transversely to the direction of the web, placed at the inlet end of the duct and arranged to direct the air supplied tangentially to the respective turning roll.

In order further to assist the turning of the pilot the arrangement according to a suitable embodiment is completed in such a way that a number of additional blast nozzles are arranged at the outlet end of the duct transversely to the direction of the web and made to direct the air supplied in the direction of travel of the web after its turning.

The invention will now be described more in detail with reference to the accompanying drawing which shows a drier tor a Web of material equipped with an arrangement according to the invention and where;

FIG. 1 shows a cross section through the end part of the drier;

FIG. 2 shows the same part as seen from one end;

FIG. 3 is a side elevation of a drier; and

FIG. 4 is an isometric view of a pilot.

In the drawing, in designates the leading end of a web 1 of material which is to be carried through a number of passages 2 of the drier D. The web of material is carried through the drier airborne by means of a drying medium blown against the web, supplied and distributed by means of a number of blast boxes 3. ,4 designates turning rolls provided for redirecting the web. 5 designates a pilot made in accordance with US. Patent No. 3,085,346 which is connected by means of a rope or tape 6 to the leading end of the web 1 for the purpose of leading the web through the said passages when threading at the beginning of drying. 7a, 7b and 7c designate battles forming return enclosures inserted in accordance with the invention in order to form -a closed, generally semicircular return or reversing duct 8 for the pilot 5. 9 designates a number of blast nozzles applied transversely to the direction of the web, placed at the inlet end of the duct and arranged to direct the air supplied tangentially to the respective turning roll. The blast nozzles are connected to a manifold 10 which in its turn is connected to an air supply line 11. In the case shown additional nozzles 12 are arranged at the outlet end of the duct, applied transversely to the direction of the Web and connected to a manifold 13. 14 designates inspection windows. As shown in FIG. 1, the air blasts cause the relatively stiff pilot 5 to be bent around a roll to open up the air-catch ing pockets in the side, the better to force the pilot forward around the roll.

What I claim is:

1. An arrangement for threading the leading end of a web of material through a treatment plant having a plural-ity of web passages and turning rolls at the ends of said passageways, comprising in combination therewith: battles forming a return enclosure around said rolls; a relatively stiff, bendable, air iloatable pilot means adapted for connection to a web to feed it through said passage- Ways and around said rolls, said pilot having air-catching pockets on the sides thereof, which pockets are opened by bending around said rolls; and means in said return enclosures for directing air blasts tangentially of said rolls intermediate said pilot and said baflles and against said pilot to bend it around a roll and advance it back int-o a passageway.

2. An arrangement for threading the leading end of a web of material through an enclosed treatment plant, comprising in combination: a main enclosure providing a web treating chamber having a plurality of horizontally disposed web passageways, turning rolls at the ends of said passageways, walls forming return enclosures around said rolls, said return enclosures forming a part of said main enclosure, a relatively stiff pilot of air floatable material attached to the front edge of the Web, means for producing opposite forwardly directed main a-ir blasts along said horizontal passageways for floating said pilot and web and moving them forward solely airborne, and airblast nozzle means at said end rolls at the inlet end of said return enclosures directed tangentially of said rolls within said return enclosures between said pilot and the wall of said return enclosures, said nozzle means operable in conjunction with said main airblast to bend said pilot and ad- Vance it around said rolls, and other airblast nozzle means at the outlet end of said return enclosures directed tangentially of said rolls to advance the pilot towards a medial position along a passageway.

References Cited by the Examiner UNITED STATES PATENTS 1,154,560 9/15 Bryant 34-156 1,338,094 4/20 Pope 162-193 2,141,578 12/38 Wellmar 34-159 2,971,267 *2/61 Berlyn 34-156 3,085,346 4/63 Allander et a1. 34-120 3,102,006 8/63 Cohn et a1. 34-156 WILLIAM F. ODEA, Acting Primary Examiner.

NORMAN YUDKOFF, Examiner. 

1. AN ARRANGEMENT FOR THREADING THE LEADING END OF A WEB OF MATERIAL THROUGH A TREATMENT PLANT HAVING A PLURALITY OF WEB PASSAGES AND TURNING ROLLS AT THE ENDS OF SAID PASSAGEWAYS, COMPRISING IN COMBINATION THEREWITH: BAFFLES FORMING A RETURN ENCLOSURE AROUND SAID ROLLS; A RELATIVELY STIFF, BENDABLE, AIR FLOATABLE PILOT MEANT ADAPTED FOR CONNECTION TO A WEB TO FEED IT THROUGH SAID PASSAGEWAYS AND AROUND SAID ROLLS, SAID PILOT HAVING AIR-CATCHING POCKETS ON THE SIDES THEREOF, WHICH POCKETS ARE OPENED BY BENDING AROUND SAID ROOLS; AND MEANS IN SAID RETURN ENCLOSURES FOR DIRECTING AIR BLASTS TANGENTIALLY OF SAID ROLLS INTERMEDIATE SAID PILOT AND SAID BAFFLES AND AGAINST SAID PILOT TO BEND IT AROUND A ROLL AND ADVANCE IT BACK INTO A PASSAGEWAY. 